Evanescent electromagnetic wave conversion lenses II

摘要

Apparatus, methods, and systems provide conversion of evanescent electromagnetic waves to non-evanescent electromagnetic waves and/or conversion of non-evanescent electromagnetic waves to evanescent electromagnetic waves. In some approaches the conversion includes propagation of electromagnetic waves within an indefinite electromagnetic medium, and the indefinite medium may include an artificially-structured material such as a layered structure or other metamaterial.

主权项

1. An electromagnetic apparatus, comprising:
a layered structure that includes alternating layers of first and second materials, the layered structure having an electromagnetic property characterized by a positive electromagnetic parameter corresponding to a first direction and a negative electromagnetic parameter corresponding to a second direction perpendicular to the first direction, the layered structure being responsive to an evanescent electromagnetic wave at a first surface region to provide a non-evanescent electromagnetic wave at a second surface region, where one of the first and second surface regions is a substantially planar surface region and the other of the first and second surface regions is a substantially nonplanar surface region, and wherein:
the layered structure is responsive to the evanescent electromagnetic wave at a first frequency with a first wavenumber to provide the non-evanescent electromagnetic wave at the first frequency with a second wavenumber, the first wavenumber corresponding to a surface parallel direction of the first surface region and the second wavenumber corresponding to a surface parallel direction of the second surface region;a first region outside the layered structure and adjacent to the first surface region defines a first phase velocity for electromagnetic radiation, and the first wavenumber is greater than the first frequency divided by the first phase velocity; anda second region outside the layered structure and adjacent to the second surface region defines a second phase velocity for electromagnetic radiation, and the second wavenumber is less than the first frequency divided by the second phase velocity.